<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			.father {
				width: 200px;
				height: 200px;
				margin: 0 auto;
				background-color: red;
			}

			.son {
				width: 100px;
				height: 100px;
				margin: 0 auto;
				background-color: pink;
			}
		</style>
	</head>
	<body>
		<div class="father">
			<div class="son">

			</div>
		</div>
		<script type="text/javascript">
			var father = document.querySelector('.father');
			var son = document.querySelector('.son');

			// father.addEventListener('mouseover', function() {
			father.addEventListener('mouseenter', function() {
				console.log('test');
			})
		</script>
	</body>
</html>
